Resources From the Sea

1. Resources From the Sea Fisheries Resources From the Sea

2. Food from the sea • The animals that are harvested vary widely from culture to culture • Polychaetes, and sea turtles • Finfish constitute 84% of the total catch • Most of the worlds food is grown on land • Only 1% of the food eaten is from the sea • Still marine resources are an important protein source • Cheap source of protein in developing countries • Japan eats 152 lb. per person and the US eats 42 lb. Resources From the Sea

3. Fishing Efficiency • We have become much more efficient in harvesting fish from the ocean putting a greater strain on the resources • Through the use of satellites, larger fishing boats, factory ships many species are overexploited or exhausted • Most fishing areas are found on the continental shelf and include both demersal and pelagic fisheries Resources From the Sea

4. World Landings Resources From the Sea

5. Landings • The largest catches come from the clupeoid fishes • Anchovies, menhaden and sardines • These fishes travel in large schools and are captured by purse seines • Used to produce fish protein concentrate (FPC) a protein supplement • Most is made into fish meal for livestock or pressed into fish oil for cosmetics, margarine and paints Resources From the Sea

6. Landings • Cods, pollock, haddock, and hakes are an important fisheries (demersal) caught using trawls • The cod fishery today is non existent on the Grand banks in the New England area • Jacks and basses along with mackerels and flatfishes provide cheap protein • Open water fisheries include several species of tuna eaten by more affluent countries raw Resources From the Sea

7. Overfishing and Fisheries Management • Fisheries are considered renewable resources, oil and gas are considered nonrenewable resources • The first step in effective management is to understand the stock size • Fish stocks grow fastest when there are neither too few nor too many individuals in a population • If too small there are not enough potential parents, if too large competition and overcrowding slow down the growth rate Resources From the Sea

8. Overfishing and Fisheries Management • Sustainable yield = the number that can be harvested and still balance the growth of the population • The highest catch that can be made without adversely affecting the population is called the maximum sustainable yield • To be effective a fisheries manager must know the growth rate and the stock size • Lastly, fishing effort must be actively regulated to allow for the maximum harvest Resources From the Sea

9. Examples of Overexploitation • Sardines on the west coast • The Peruvian anchovy • Northern Bluefin Tuna • Less than 10% of their former numbers in the northern Atlantic • Swordfish is close to commercial extinction • In 1995 88% of the fish caught by the US fishing fleet were too young to have reproduced Resources From the Sea

10. New Fisheries • With all this pressure on traditional fisheries many new fisheries are being discovered • Dolphinfish changed to mahi mahi, squid changed to calamari • Surimi, changing unappealing fish through spices and preseratives into imitation crab, lobster, crabs, shrimp, and scallops • The fish which is commonly used is Alaskan Pollock • Yet to be exploited fisheries include lantern fishes, pelagic crabs and other cephalopods Resources From the Sea

11. Resources From the Sea

12. Resources From the Sea